The invention relates to a method for eliminating leafstalks from a harvested stream in a berry harvesting machine, an extraction conveyor and an elimination system for implementing that method, and a berry harvesting machine including such an extraction conveyor or such an elimination system.
The invention applies to the field of the mechanised harvesting of fruit growing on tree or bushes, such as grapes, berries, coffee beans, olives or other fruit in particular fruit growing in bunches.
Grapes are conventionally harvested by a shaker assembly that straddles a row of plants to detach the harvest. The harvested stream obtained is then conveyed through the machine to be stored in at least one hopper provided for this purpose or in an associated trailer.
However, because of the action of the shaker assembly, the harvested stream contains, in addition to detached fruit, in particular juice, leaves, leafstalks, wood particles, and bunches of fruit of various sizes.
To eliminate material other than fruit, in particular leaves and wood particles, harvesting machines include a cleaning system which is operable to eliminate said material from the stream by suction before storage.
Harvesting machines can also carry a sorting device that in particular separates the harvested streamed produce as a function of the size of the constituents of said stream. Accordingly, by providing for such sorting, it is possible to separate the portion including large constituents, such as bunches and leaves, in one direction and the rest of the constituents, such as juice, detached fruit, small pieces of waste and leafstalks, in another direction. After this sorting, a suction cleaning device can be oriented over the first portion to remove the leaves without sucking up detached fruit and juice.
Moreover, the search for quality in vinification demands the elimination of leafstalks contained in the harvested stream. However, the prior art makes no provision for such elimination in the harvesting machine either during cleaning or during sorting.
In fact, suction cleaning is based on the differing lift of the constituents of the stream and sorting is based on the differing sizes of said constituents. Now, in the case of leafstalks, their lift and their size are not sufficiently different from those of the berries for the prior art devices to be able to clean or sort one without the other without losing a substantial quantity of fruit.
The invention aims to improve on the prior art by proposing in particular a method for eliminating leafstalks from a harvested stream, said method being implemented in the harvesting machine on recovering the detached berries.